What you need to know before getting a pet turtle

And if you think you can just buy a "penny turtle", think again because they don't exist. 

"They sound cute and cuddly but they actually don't exist," NT Parks and Wildlife ranger Clare Pearce told the ABC.

Instead, Clare says people are probably buying hatchling freshwater turtles, which can grow quite large.  "They will outgrow most aquariums or tanks within a couple of years and either need a bigger tank or a pond — and they'll definitely need a pond by the time they're five or six years old," she said. 

As well as their size, turtles have a long lifespan. "Depending on the species, you could be looking at anywhere from 20 to 25 and 40 years old," Clare said. "They're a bit like the long-term commitment of keeping a cockatoo as a pet."